WO2014157964A1 - Resin composition for polarizer protecting film, polarizer protecting film, polarizing plate comprising same, and method for manufacturing polarizing plate - Google Patents

Abstract

The present invention relates to a resin composition for a polarizer protecting film, a polarizer protecting film, a polarizing plate comprising the same, and a method for manufacturing the polarizing plate and, more particularly, to a resin composition for a polarizer protecting film exhibiting high hardness and excellent characteristics, a polarizer protecting film, a polarizing plate comprising the same, and a method for manufacturing the polarizing plate. The polarizing plate of the present invention exhibits excellent hardness, flexibility, and optical characteristics, and thus can be useful in various fields.

Description

 【Specification】

 [Name of invention]

 Resin composition for polarizer protective film, polarizer protective film, polarizing plate containing same and manufacturing method of polarizing plate

 Technical Field

 The present invention relates to a resin composition for a polarizer protective film, a polarizer protective film, a polarizing plate including the same, and a manufacturing method of the polarizing plate. More specifically, the present invention relates to a resin composition for a polarizer protective film, a polarizer protective film, a polarizing plate including the same, and a method of manufacturing the polarizing plate, which exhibit excellent physical and optical properties.

 This application is filed with the Korean Patent Application No. 10-2013-00330 No. 10-2013-00330 filed with the Korean Patent Office on March 27, 2013, and the Korean Patent Application No. 10-2013-0033003, 2014, filed with the Korean Patent Office on March 27, 2013. Claims the benefits of Korean Patent Application No. 10-2014-0035586 filed with the Korean Patent Office on March 26, 2014 and Korean Patent Application No. 10-2014-0035587 filed with the Korean Patent Office on March 26, 2014 All of the content is included in this specification.

 Background Art

Liquid crystal displays (LCDs) are one of the most widely used flat panel displays at present. In general, a liquid crystal display has a structure in which a liquid crystal layer is enclosed between a thin film transistor (TFT) array substrate and a color filter substrate. When applying an electric field to the electrode ^■ present on the array substrate and the color filter substrate is changed to an arrangement of liquid crystal molecules in the liquid crystal layer enclosed therebetween, and displays images by using them.

 On the other hand, the polarizing plate is provided outside the array substrate and the color filter substrate. The polarizer may control polarization by selectively transmitting light in a specific direction among light incident from the backlight and light passing through the liquid crystal layer.

 The polarizing plate generally has a structure in which a protective film for supporting and protecting the polarizer is adhered to a polarizer capable of polarizing light in a specific direction.

As said protective film, it consists of triacetyl cellulose (TAC). Films are widely used. In addition, a protective film has been proposed for coating a hard coat layer to achieve a film having properties of high hardness and wear resistance _. On the other hand, these days, the use of liquid crystal devices has become widespread, and they are used in devices of various fields, and interest in improving the hardness and thinning of polarizing plates is increasing.

 For this necessity, a polarizing plate in which a TAC film is omitted and a protective layer is formed on the surface of the polarizer using a photopolymerizable compound is proposed in JP-A-2005-010329 and the like. However, there is still a need for development of a polarizing plate having sufficient hardness, low thickness to allow thinning, and sufficient flexibility to be suitable for mass production processes.

 [Content of invention]

 Problem to be solved

 In order to solve the above problems, the present invention exhibits high hardness and high transparency, and can be thinned, and at the same time exhibits excellent flexibility, a resin composition for a polarizer protective film that does not generate curl or crtack, a polarizer protective film, and the like. It provides a polarizing plate and a manufacturing method of a polarizing plate.

 [Measures of problem]

 In order to solve the above problems, the present invention provides a resin composition comprising a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and a binder containing a acrylate elastic polymer and a photoinitiator. To provide.

 The present invention also provides a polarizer protective film comprising a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and a cured resin with an acrylate elastic polymer.

 In addition, the present invention, a polarizer; And a protective film provided on at least one surface of the polarizer, wherein the protective film is a polyfunctional acrylate monomer, cured with an acrylate oligomer having an elongation of 5 to 200%, and an acrylate elastic polymer. It provides a polarizing plate containing a resin.

In addition, the present invention is a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and an acrylate based on a release film A binder comprising an elastic polymer; And applying a resin composition comprising a photoinitiator;

 Photocuring the coated resin composition fire to form a protective film; It provides a method of manufacturing a polarizing plate comprising the step of laminating and bonding the protective film on one side of the polarizer.

 【Effects of the Invention】

 According to the polarizing plate of the present invention, a protective film which exhibits high hardness, scratch resistance and high transparency and which does not generate curl or cracks with excellent workability can be usefully applied to various display devices. In addition, it is possible to reduce the thickness by applying to a base film such as a TAC film without a separate coating. In particular, since it does not include a stretched film, the retardation value is low enough to be substantially close to zero, and can be used for various devices in which such a low retardation value is required, as well as the polarizer protective film, without limitation of use.

 In addition, there is an advantage that can be applied to large area or curved display by showing excellent processability and flexibility.

 [Specific contents to carry out invention]

 The resin composition of the present invention is a binder comprising a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and an acrylate elastic polymer; And photoinitiators.

 The polarizer protective film of the present invention contains a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and a cured resin with an acrylate elastic polymer.

 Polarizing plate of the present invention, a polarizer; A protective film provided on at least one surface of the polarizer, wherein the protective film is a polyfunctional acrylate monomer, an acrylate-based oligomer having an elongation of 5 to 200%, and a cured resin with an acrylate-based elastic polymer. It includes.

Method for producing a polarizing plate of the present invention, a binder comprising a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and an acrylate-based elastic polymer on a release film; And optical Applying a resin composition comprising an initiator; Photocuring the applied resin composition to form a protective film; And laminating the protective film on one surface of the polarizer and adhering the protective film.

 As the invention allows for various changes and numerous modifications, particular embodiments will be illustrated and described in detail below. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

 Hereinafter, the resin composition for polarizer protective film of this invention, a polarizer protective film, the polarizing plate containing this, and the manufacturing method of a polarizing plate are demonstrated in detail. In the present specification, the acrylate-based means both acrylates and methacrylates, or derivatives in which substituents are introduced into acrylates or methacrylates.

 The polarizer protective film according to an aspect of the present invention includes a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and a cured resin with an acrylate elastic polymer.

 The said polarizer protective film is used for the use which protects a polarizer from an external arc.

 Commonly used polarizer protective films include polyesters such as polyethylene terephthalate (PET), cyclic olefin copolymers (COC), polyacrylates (polyacrylates, PACs), and polycarbonates. (polycarbonate, PC), polyethylene (PE), polymethylmethacrylate (PMMA), polyetheretherketon (PEEK), polyethylenenaphthalate (PEN), polyetherimide PEI The base material which consists of a polyimide (PI) or triacetyl cellulose (TAC) etc. is mentioned.

Among the above substrates, triacetyl cellulose (TAC) film is particularly optical. It is excellent in characteristics and used a lot. By the way, when the TAC film is used alone, the surface hardness is weak and vulnerable to humidity, it is necessary to add a functional coating layer such as hard coating. However, if the functional coating layer is further included in this way, the overall thickness of the protective film is increased, which may not meet recent thinning requirements, and additional coating may cause curl or crack in the film. Accordingly, the present invention replaces the TAC film that is commonly used, and provides a protective film having a low thickness so as to meet a sufficient hardness and thinning trend without including a separate coating layer. In addition, the protective film of the present invention exhibits excellent optical properties required for the polarizer protective film, it may exhibit excellent flexibility to facilitate production, processing, storage and transport. In addition, since the stretched film is not included, the retardation value is substantially low to nearly zero, and can be used for various devices in which such a low retardation value is required, as well as the polarizer protective film, without limitation of use.

 In addition, there is an advantage that can be applied to large area or curved display by showing excellent processability and flexibility.

 The polarizer protective film of the present invention includes a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and a cured resin with an acrylate elastic polymer.

 The multifunctional acrylate monomer means that the acrylate functional group contains two or more and has a molecular weight of less than l, 000 g / mol. More specifically, for example, nucleic acid diol diacrylate (HDD A), tripropylene glycol diacrylate (TPGDA), ethylene glycol diacrylate (EGDA), trimethylolpropane triacrylate (TMPTA), trimethylolpropaneethoxy Triacrylate (TMPEOTA), Glycerol ¾ Propoxylated Triacrylate (GPTA), Pentaerythritol Tetraacrylate (PETA), or Dipentaerytri may include nuxaacrylate (DPHA) and the like. The protective film is not limited to this. The multifunctional acrylate monomer crosslinks with the acrylate oligomer and the acrylate-based carbon polymer, which will be described later, and serves to provide a constant pencil strength and wear resistance to the protective film.

The polyfunctional acrylate monomers alone or different Type can be used in combination.

 The acrylate-based oligomer is an acrylate having an elongation of about 5 to about 200%, or about 5 to about 100%, or about 10 to about 50%, as measured by ASTM D638. It means oligomer which has two or more. When the elongation of the acrylate oligomer has the above range, it may exhibit excellent flexibility and elasticity without deteriorating mechanical properties. The acrylate oligomer that satisfies the elongation range as described above is excellent in flexibility and elasticity to form the acrylate monomer and the acrylate-based elastomer and a cured resin, and the flexibility and curl characteristics of the protective film including the same Etc. can be given.

 According to one embodiment of the present invention, the weight average molecular weight of the acrylate-based oligomer is about 1,000 to about 10,000 g / mol, or about 1,000 to about 5,000 g / mol, or about 1,000 to about 3,000 g / m It can have a range.

 According to one embodiment of the present invention, the acrylate oligomer may be an acrylate oligomer modified with at least one of ethylene oxide, propylene oxide, or caprolactone. . When the modified acrylate oligomer is used, flexibility may be further imparted to the acrylate oligomer by modification, thereby increasing curl characteristics and flexibility of the protective film.

 The acrylate oligomers may be used alone or in combination with each other.

The acrylate-based elastic polymer has excellent flexibility and elasticity, and may include a acrylate functional group to crosslink and polymerize with the multifunctional acrylate monomer and the acrylate oligomer to form a crosslinked copolymer structure. Therefore, the protective film formed by using the resin composition including the same, it is possible to secure a high elasticity or flexibility while securing mechanical properties, it is possible to minimize the curl (curl) or crack (crack) generation. The protective film according to the present invention includes a cured resin in which the acrylate-based elastic polymer is cross-polymerized together with the above-described multifunctional acrylate-based monomer and acrylate-based oligomer, thereby exhibiting high hardness and at the same time having flexibility. Therefore Accordingly, it can be applied as a multifunctional polarizer protective film by acting as a hard coating layer while at the same time functioning as a polarizer protective layer without a separate functional coating layer.

 According to one embodiment of the invention, the acrylate-based elastic polymer has an elongation of about 5 to about 200%, or about 5 to about 100%, or about 10 to about 50%, as measured by ASTM D638 Can be. When the elongation of the acrylate-based elastic polymer has the above range it can exhibit excellent flexibility and elasticity without deterioration of mechanical properties.

 According to an embodiment of the present invention, the average molecular weight of the acrylate-based elastic polymer is in the range of about 100,000 to about 800,000 g / mol, or about 150,000 to about 700,000 g / mol, or about 180,000 to about 650,000 g / m. It can have If the weight average molecular weight of the acrylate-based elastic polymer is too small, the flexibility and elasticity of the protective film manufactured using the same may not be sufficient. If the weight average molecular weight is too large, compatibility with Daron material is lowered and uniform. It may be difficult to obtain a composition, and it may be desirable to have an increase average molecular weight in the above-described range in this respect.

 One example of the acrylate-based elastic polymer may be polyrotaxane.

 In general, poly-rotaxane refers to a compound in which a dumbbell shaped molecule and a cyclic compound are structurally interposed, such that the dumbbell shaped molecule is a constant linear molecule and such linear A blocking group disposed at both ends of the molecule, the linear molecule penetrating the interior of the cyclic compound, the cyclic compound can move along the linear molecule, and escape from the blocking group.

 According to one embodiment of the present invention, the polyrotasein is a cyclic compound in which a lactone compound in which an acrylate compound is introduced at the terminal is bonded; Linear molecules penetrating the cyclic compound; And a rotasein compound disposed at both ends of the linear molecule and including a blocking group to prevent the cyclic compound from being separated.

The cyclic compound may penetrate or surround the linear molecule It may be used without any limitation as long as it has a degree of size, and may include functional groups such as hydroxyl group, amino group, carboxyl group, thiol group or aldehyde group which can react with other polymers or compounds. Specific examples of such cyclic compounds include α-cyclodextrin, β-cyclotextrin, γ-cyclodextrin, or a combination thereof.

 In addition, as the linear molecule, a compound having a straight chain form having a molecular weight of a predetermined or more may be used without great limitation, but a polyalkylene compound or a polycaprolactone group may be used. Specifically, a polyoxyalkylene compound containing an oxyalkylene repeating unit having 1 to 8 carbon atoms or a polycaprolactone group having a lactone repeating unit having 3 to 10 carbon atoms may be used. In addition, such linear molecules may have a weight average molecular weight of about 1,000 to about 50,000 g / n) 1. If the weight average molecular weight of the linear molecule is too small, the mechanical properties or self-healing ability of the protective film manufactured using the same may not be sufficient. If the weight average molecular weight is too large, the compatibility of the protective film to be manufactured may be degraded or the appearance may be poor. Properties and uniformity of materials can be greatly reduced.

 On the other hand, the containment group can be appropriately adjusted according to the properties of the polyrotasein to be prepared, for example, one selected from the group consisting of dinitrophenyl group, cyclodextrin group, adamantane group, trityl group, fluorescein group and pyrene group or Two or more kinds can be used.

 Another example of the acrylate-based elastic polymer is a urethane-based acrylate polymer. The urethane-based acrylate polymer has a form in which a urethane-based acrylate oligomer is connected to the main chain of the acrylic polymer by a defect.

 The protective film of this invention is the polyfunctional acrylate-type monomer mentioned above, 5-

An acrylate-based oligomer and an acrylate-based elastic polymer having an elongation of 200% include a cured resin cured by ultraviolet rays. In addition, the protective film of this invention does not contain a triacetyl cellulose (TAC) component.

According to an embodiment of the present invention, when the total weight of the cured resin is 100 parts by weight, the polyfunctional acrylate monomer is about 20 to about 70 By weight, about 20 to about 70 parts by weight of the acrylate oligomer having an elongation of 5 to 200%, and the acrylate-based elastic polymer may be cured in the range of about 1 to about 50 parts by weight.

 Or when the total weight of the cured resin is 100 parts by weight, the polyfunctional acrylate monomer is about 40 to about 60 parts by weight, and the acrylate oligomer having 5 to 200% of the god is about 20 to about 50 parts by weight. By weight, the acrylate-based elastic polymer may be cured in the range of about 1 to about 30 parts by weight.

 When the three components are cured in the above weight part range, the protective film of the present invention may have layered flexibility without deterioration of mechanical properties.

 The protective film of the present invention includes a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and a cured resin in which an acrylate-based elastic polymer is cured, thereby providing high hardness and thinning without deterioration of optical properties. It is possible. In addition, the surface hardness and scratch resistance is excellent without a separate functional coating layer such as hard coating. In addition, excellent flexibility, impact resistance and flexibility are ensured, making it suitable for large area or curved displays. In addition, since it includes a cured resin layer that is not a stretched film, the phase difference value is substantially close to zero, and can be used for various display devices that require a low phase difference value as well as a polarizer protective film, without limitation of use.

 According to an embodiment of the present invention, the protective film of the present invention may further include inorganic fine particles. The inorganic fine particles may be included in a form dispersed in the cured resin.

 The inorganic fine particles may be inorganic fine particles having a nanoscale particle diameter, for example, nanoparticles having a particle diameter of about 100 nm or less, or about 10 to about 100 nm, or about 10 to about 50 nm. In addition, the inorganic fine particles may include, for example, silica fine particles, aluminum oxide particles, titanium oxide particles, or zinc oxide particles.

By containing the said inorganic fine particle, the hardness of a protective film can be improved further. According to an embodiment of the present invention, when the total weight of the cured resin is 100 parts by weight, the inorganic fine particles may include about 1 to about 50 parts by weight, or may include about 1 to about 40 parts by weight. . By including the inorganic fine particles in the above range, a protective film excellent in both high hardness and flexibility can be provided.

 According to one embodiment of the invention, the protective film has a thickness of about 10 or more, for example about 10 to about 200, or about 10 to about 100m, or about 10 to about 50 / im, or about 10 to It may have a thickness of about 40 / in, or about 10 to about 30. According to the present invention, by having the thickness as described above can be thinner than a film including a separate coating layer, it is possible to provide a high hardness protective film without curling or cracking.

 As described above, the polarizer protective film of the present invention includes the polyfunctional acrylate monomer, an acrylate oligomer having 5 to 200% of an acrylate, an acrylate elastomer, a photoinitiator, and optionally inorganic fine particles and an organic solvent. The resin composition to be photocured can be formed. According to another aspect of the present invention, a binder comprising a multifunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and an acrylate elastic polymer; And a photoinitiator.

 More detailed description of the multifunctional acrylate monomer, the acrylate oligomer having an elongation of 5 to 200%, and the acrylate elastic polymer is as described above in the protective film.

According to an embodiment of the present invention, when the total weight of the binder including the multifunctional acrylate monomer, the acrylate oligomer having an elongation of 5 to 200%, and the acrylate elastic polymer is 100 parts by weight, The polyfunctional acrylate monomer may include about 20 to about 70 parts by weight, or may include about 40 to about 60 parts by weight. By including the polyfunctional acrylate monomer in the above range, a protective film excellent in both high hardness and flexibility can be formed. When the content of the multifunctional acrylate monomer is lower than 20 parts by weight, the crosslinking density is lowered, so that pencil hardness or The mechanical properties of the coating film, such as scratch resistance, may be lowered, and when it is more than 70 parts by weight, the coating film is brittle and cannot have sufficient flexibility.

 According to one embodiment of the present invention, when the total amount of the binder is 100 parts by weight, the acrylate oligomer may include about 20 to about 70 parts by weight, or about 20 to about 50 parts by weight. have. When the content of the acrylate oligomer is lower than 20 parts by weight. The coating may not have sufficient flexibility, and when using 70 parts by weight or more, the mechanical properties may be insufficient.

 According to the resin composition of the present invention, the binder component includes a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and an acrylate elastic polymer, and the polyfunctional acrylate monomer and acryl The cured resin cured by polymerizing a latent oligomer and an acrylate-based elastic polymer may form a protective film having a thin thickness without deteriorating optical properties. In addition, the protective film thus formed is excellent in surface hardness and scratch resistance even without a separate functional coating layer such as hard coating. In addition, excellent flexibility and flexibility can be achieved. In addition, since it includes a cured resin layer that is not a stretched film, the phase difference value is low enough to be substantially close to 0, and may be used for various display devices requiring low phase difference values as well as films for polarizer protection, without limitation of use.

According to one embodiment of the invention, including the total weight of the binder to 100 parts by weight, may include a acrylate-based elastic ⁱ polymeric portion from about 1 to about 50 parts by weight, or parts of about 1 to about 30 wt. can do. By including the acrylate-based elastic polymer in the above range it is possible to form a protective film excellent in both hardness and flexibility.

The above-mentioned multifunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and a binder containing an acrylate-based elastic polymer may be polymerized with each other by ultraviolet light to form a cured resin. The resin composition according to the present invention includes the acrylate-based elastic polymer together with the above-described multifunctional acrylate-based monomer and acrylate-based oligomer, and thus the protective film formed by curing it exhibits high hardness. At the same time, it can be flexible. Accordingly, it can be applied as a multifunctional polarizer protective film by acting as a hard coating layer while also functioning as a polarizer protective layer without a separate functional coating layer.

 Examples of the photoinitiator include 1-hydroxycyclohexyl-phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone,

 2-hydroxy-1- [4- (2-hydroxyethoxy) phenyl] -2-methyl-1-propanone,

Methylbenzoylformate, α, _α -dimethoxy- _α -phenylacetophenone,

2-benzoyl-2- (dimethylamino) -1- [4- (4-morpholinyl) phenyl] -1-butanone,

2-methyl 小 [4 ᅳ (methylthio) phenyl] -2- (4-morpholinyl) -1-propanone

Diphenyl (2,4,6-trimethylbenzoyl) -phosphine oxide, or bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, and the like. Commercially available products include Irgacure 184, Irgacure 500, Irgacure 651, Irgacure 369, Irgacure 907, Darocur 1173, Darocur MBF, Irgacure 819, Darocur TPO, Irgacure 907, and Esacure KIP '100F. These photoinitiators can be used individually or in mixture of 2 or more types different from each other. According to an embodiment of the present invention, when the total weight of the binder is 100 parts by weight, the photoinitiator may include about 1 to about 10 parts by weight, or about 1 to about 8 parts by weight.

 The resin composition of the present invention may be used in the form of a solvent-free solvent containing a solvent when the formulation of each component is uniform and has an appropriate viscosity and there is no problem in the coating process.

 On the other hand, the resin composition of the present invention may further include an organic solvent for uniform blending and coating properties of each component.

Examples of the valuable solvent include alcohol solvents such as methane, ethanol, isopropyl alcohol and butane, 2-methoxyethane, alkoxy alcohol solvents such as 2-ethoxyethanol and 1-methoxy-2-propanol, Ketone solvents such as acetone, methyl ethyl ketone, meptyl isobutyl ketone methyl propyl ketone, cyclonucleanone propylene glycol monopropyl ether, propylene glycol monomethyl ether ethylene glycol monoethyl ether, ethylene glycol monopropyl ether ethylene glycol monobutyl ether, di Ethylene Glycol Monomethyl Ether Ether solvents such as diethyl glycol monoethyl ether, diethyl glycol monopropyl ether, diethyl glycol monobutyl ether, diethylene glycol-2-ethyl nucleosil ether, aromatic solvents such as benzene, toluene and xylene Can be used or mixed.

 According to one embodiment of the present invention, the content of the organic solvent is not particularly limited because it can be variously adjusted within a range that does not lower the physical properties of the resin composition.

 According to an embodiment of the present invention, the resin composition of the present invention may further include inorganic fine particles. The inorganic fine particles may be included in the resin composition in a form dispersed in the multifunctional acrylate monomer. The inorganic fine particles may be inorganic fine particles having a particle size of nanoscale, for example, nanoparticles having a particle diameter of about 100 nm or less, or about 10 to about 100 nm, or about 10 to about 50 nm. In addition, the inorganic fine particles may include, for example, silica fine particles, aluminum oxide particles, titanium oxide particles, or zinc oxide particles.

 By containing the said inorganic fine particle, the hardness of a protective film can be improved further.

 According to an embodiment of the present invention, when the resin composition further includes inorganic fine particles, when the total weight of the binder is 100 parts by weight, the inorganic fine particles may include about 1 to about 50 parts by weight, or About 1 to about 40 parts by weight. By including the said inorganic fine particle in the said range, the protective film excellent in both high hardness and flexibility can be formed.

 On the other hand, the resin composition is a UV absorber, in addition to the above-mentioned polyfunctional acrylate monomer, acrylate-based oligomer having an elongation of 5 to 200%, acrylate-based elastic polymer, inorganic fine particles, photoinitiator, organic solvent, Additives commonly used in the art to which the present invention pertains include surfactants, anti-yellowing agents, leveling agents, antifouling agents, and the like. In addition, since the content can be variously adjusted within a range that does not lower the physical properties of the protective film of the present invention, it is not particularly limited.

According to one embodiment of the present invention, for example, the resin composition The additive may include a surfactant, and the surfactant may be a 1 to 2 functional fluorine acrylate, a fluorine surfactant, or a silicone surfactant. In this case, the surfactant may be included in the form of being dispersed or crosslinked in the cured resin.

 Further, the additive may include a yellowing inhibitor, and the yellowing inhibitor may include a benzophenone compound or a benzotriazole compound.

 As described above, a binder comprising a multifunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and an acrylate elastic polymer, a photoinitiator, and optionally an organic solvent, inorganic fine particles, and other additives. A polarizer protective film can be formed by photocuring the resin composition containing a.

 According to another aspect of the invention, the polarizer; And a protective film provided on at least one surface of the polarizer, wherein the protective film is a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and an acrylate elastic polymer. Provided is a polarizing plate containing a cured resin.

According to another aspect of the invention, on a release film _. A binder comprising a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and an acrylate elastic polymer; And applying a resin composition comprising a photoinitiator; Photocuring the applied resin composition to form a protective film; And it provides a method of manufacturing a polarizing plate comprising the step of laminating and bonding the protective film on one side of the polarizer.

First, a binder comprising a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and an acrylate elastic polymer; And the resin composition containing a photoinitiator is apply | coated on a release film. The detailed description about the component contained in the said resin composition is as having demonstrated in the said polarizer protective film. The resin composition may optionally further include an organic solvent, inorganic fine particles, additives, and the like. The release film may be used without limitation as long as it is commonly used in the art to which the present invention pertains. According to one embodiment of the invention, the release film is a polyolefin-based film such as polyester film, polyethylene film, polyethylene terephthalate film, polypropylene film. Alternatively, the film may be a Teflon-based film, and preferably, the film may be release-treated with a silicone-based resin, melamine-based resin, or urea-based resin to facilitate peeling. The thickness of the release film is not particularly limited, but a release film having a thickness of about 20 to about 200 may be mainly used.

 The release film may be removed by peeling after curing the resin composition and before attaching the protective film to the polarizer. Or may be removed after attachment to the polarizer to favor transport and storage or the like.

 The method of applying the resin composition is not particularly limited as long as it can be used in the technical field to which the present technology belongs, for example, bar coating method, knife coating method, roll coating method, blade coating method, die coating method, micro gravure coating method. Method, comma coating method, slot die coating method, lip coating method, or solution casting method may be used.

 Next, a protective film can be formed by irradiating an ultraviolet-ray to the apply | coated resin composition and performing a photocuring reaction. Before irradiating the ultraviolet rays, a process of flattening the coated surface of the resin composition and drying to volatilize the solvent included in the composition may be further performed.

The irradiation amount of ultraviolet rays may be, for example, about 20 to about 600 mJ / cm ² . The light source for ultraviolet irradiation is not particularly limited as long as it can be used in the art to which the present technology belongs, and for example, a high pressure mercury lamp, a metal halide lamp, a black light fluorescent lamp, or the like can be used.

The resin. After the composition is completely cured, a polarizer protective film formed of a single layer without a base film such as TAC or a separate coating layer can be obtained. According to the polarizer protective film of the present invention, the protective film is applied to a separate release film and cured, not directly formed on the polarizer, so that it is not affected by the shrinkage of the substrate and does not generate curls or cracks and forms a high hardness protective film. can do. In addition, it exhibits a low phase difference value, and has a light transmittance and a haze. It is possible to provide a high hardness polarizer protective film without deterioration in optical properties required for the polarizer protective film.

 The protective film of the present invention exhibits high hardness, flexibility, scratch resistance, high transparency, and can be used as a single layer film for polarizer protection and can be usefully used in various display devices.

 In the present invention, the protective film may be included only on one side of the polarizer, or both sides of the polarizer.

 The polarizer exhibits a property of extracting only light vibrating in one direction from incident light while vibrating in various directions. This property can be achieved by stretching polyvinyl alcohol (PVA) absorbing iodine with strong tension. For example, more specifically, swelling to swell the PVA film in an aqueous solution, dyeing with a dichroic material imparting polarization to the swelled PVA film, stretching the dyed PVA film The polarizer may be formed through a stretching step of arranging the dichroic dye materials side by side in the stretching direction, and a complementary color step of correcting the color of the PVA film subjected to the stretching step. However, the polarizing plate of the present invention is not limited thereto.

 The polarizing plate of the present invention includes a protective film provided on at least one surface of the polarizer.

 The protective film may have a thickness of about 10 / m or more, for example about 10 to about 100, or about 10 to about 50, or about 10 to about 4 () // m, or about 10 to about 30. .

 In addition, the total thickness of the polarizing plate of the present invention may be about 45 / im or more, for example about 45 to about 250 // m, or about 50 to about 120 / Λπ, or about 50 to about 100. According to the present invention, it is possible to achieve a high hardness without the occurrence of curl or crack while having a thin thickness as described above.

The protective film comprises a curable resin with a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200% and an acrylate elastomer, and optionally further contains inorganic fine particles dispersed in the cured resin. It may include. A more detailed description of this and the above protection The method for producing the film is as described for the protective film for polarizer. According to an embodiment of the present invention, the polarizing plate of the present invention may further include an adhesive layer provided between the polarizer and the protective film.

 The adhesive layer may include a polarizer adhesive, which may have transparency and maintain polarization characteristics of the polarizer. Usable adhesives are not particularly limited as long as they are known in the art. For example, there are one-component or two-component polyvinyl alcohol (PVA) adhesives, acrylic adhesives, polyurethane adhesives, epoxy adhesives, styrene butadiene rubber (SBR) adhesives, or hot melt adhesives. It is not limited only to an example.

 The thickness of the adhesive layer may be about 0.1 to about 10 kPa, or about 0.1 to about 5, but the present invention is not limited only to these examples.

 Next, the polarizing plate of this invention can be obtained by laminating the formed protective film on a polarizer using an adhesive agent, and adhering. At this time, the release film is. After curing of the resin composition, the protective film may be removed by being selectively peeled off before or after adhering to the polarizer.

 According to one embodiment of the present invention, the protective film may be attached to both sides of the polarizer.

 According to another embodiment of the present invention, the protective film is attached only to one side of the polarizer, the other side may be attached to another general purpose film such as TAC. In this case, the protective film may be positioned at the outermost side facing the user. As described above, the protective film of the present invention exhibits high hardness, scratch resistance, and optical properties suitable for the outermost layer.

 The protective film of the present invention exhibits excellent properties that can replace the TAC film, and thus the polarizing plate including the same may have excellent pencil hardness, curling properties, flexibility and optical properties.

For example, according to one embodiment of the present invention, the polarizing plate of the present invention, when exposed to room temperature for 24 hours, when placed in a plane, the average value of the distance from each corner or one side plane of the polarizing plate is about 3mm Or about 2 mm or less, or about 1 mm or less. In addition, the pencil hardness of the polarizing plate of the present invention may be 1H or more, 2H or more, or 3H or more.

 In addition, the polarizing plate of the present invention may have a single transmittance of 40% or more, or 42% or more.

 In addition, the polarizing plate of the present invention may not generate a stack when it is wound around the cylindrical mandrel having a diameter of 15mm, 12mm, or 5mm.

 In addition, the protective film provided in the polarizing plate of the present invention may exhibit a plane direction retardation value of 0 to 1 nm, 0 to a6 nm, or 0 to 0.5 nm.

 The polarizing plate provided with such a protective film of this invention can be utilized in various fields. For example, it can be used for a mobile communication terminal, a smart phone, other mobile devices, a display device, an electronic blackboard, an outdoor billboard, and various display units. According to an embodiment of the present invention, the polarizing plate may be a twisted nematic (TN), super twisted nematic (STN) liquid crystal, an in-plane switching (IPS), a super-IP S, or a fringe field switching (FFS). It may be a polarizing plate for a horizontal alignment mode such as, or may be a polarizing plate for a vertical alignment mode. Hereinafter, the operation and effects of the invention will be described in more detail with reference to specific examples of the invention. However, these embodiments are only presented as an example of the invention, whereby the scope of the invention is not determined. <Example>

 Preparation of Polyrotasein

 Preparation Example 1

50 g of polyrotaxane polymer A1000, Advanced Soft Material INC] grafted with caprolactone was added to the reactor, and then Karenz-AOI [2-acryloylethyl isocyanate, Showadenko] 4.53 g, Dibutyltin dilaurate [DBTDL, Merck Co., Ltd.] 20 mg, 110 g of hydroquinone monomethylene ether and 315 g of methyl ethyl ketone were added and reacted at 70 ^° C. for 5 hours to include a cyclodextrin having a polycaprolactone group bonded with an acrylate compound at its end as a cyclic compound. A polyrotasein polymer was obtained. The weight average molecular weight of the obtained polyrotasein polymer is 600,000 g / mol, The elongation measured by ASTMD638 was 20%. Manufacture of protective film

 Example 1

 Trimethylolpropane triacrylate (TMPTA) 50g, DPCA120 (Nippon

Kayaku, caprolactone modified 6 functional acrylate, 12% elongation measured by ASTM D638, Mw 1,950) 30g, PU3400 (Miwon, ethylene oxide modified 3 functional acrylate, 20% elongation measured by ASTM D638, 10g, Mw 2,500) A coating solution was prepared by mixing 10 g of polyrotasein of Preparation Example 1, 6 g of a photoinitiator (trade name Darocur TPO), 3 g of a UV absorber (trade name Chimassorb 81), and MEK lOg, and bar coating the PET release film. It was dried for 2 minutes at 60 ^° C, and then irradiated with black UV in a nitrogen atmosphere to obtain a protective film having a thickness of 25. Example 2

 TMPTA 50g, DPCA12030g, TA604AU (Japan oil and fat, ethylten oxide modified

Trifunctional acrylate, 49% elongation measured by ASTM D638, 15 g of Mw 2,300), 5 g of polyrotasein of Preparation Example 1, 6 g of photoinitiator (trade name Darocur TPO), 3 g of UV absorber (trade name Chimassorb 81), MEK lOg Combined to prepare a coating solution and bar coating on PET release film. It was dried for 2 minutes at 60 ^° C, and then irradiated with black UV in a nitrogen atmosphere to obtain a protective film having a thickness of 25. Example 3

TMPTA 50g, PU3400 10g, TA604AU 20g, 8BR-500 (Daesung Chemical, 7% elongation measured by ASTM D638, Mw 180,000) 20g, Photoinitiator (trade name Darocur TPO) 6g, UV absorber (trade name Chimassorb 81) 3g, MEK lOg The coating solution was prepared by mixing and bar coating the PET release film. After drying for 2 minutes at 60 ^° C, black UV irradiation in a nitrogen atmosphere to obtain a protective film having a thickness of 25 / / m. Comparative Example 1

TMPTA 50g, EB1290 (SK Cytec, 6 functional urethane acrylate, ASTM 50% elongation measured by D638, Mw 1,000) 50g, 6g photoinitiator (trade name Darocur TPO), 3g UV absorber (trade name Chimassorb 81), MEK 100g was prepared to prepare a coating solution and bar-coated on a TAC film of 40 thickness. After drying at 60 ^° C. for 2 minutes, black UV was irradiated in a nitrogen atmosphere to obtain a protective film including a coating layer having a thickness of 6 on the TAC film.

 Example 4

 The protective film prepared in Example 1 was laminated by laminating with a PVA film so that the thickness of the adhesive layer was approximately 1 / using an acrylic adhesive, and the PET release film was peeled off.

 On the other side of the PVA, a polarizing plate was prepared by bonding a 40-thick TAC in the same way. Example 5

 One side of the PVA film was attached to the protective film of Example 2 and the other side was attached a TAC film of 40 thickness to prepare a polarizing plate in the same manner as in Example 4. Example 6

 A polarizing plate was prepared in the same manner as in Example 4 by attaching the protective film of Example 3 to one side of the PVA film and attaching a TAC film of 40 thickness to the other side. Comparative Example 2

One side of the PVA film was attached to a TAC film formed with a coating of Comparative Example 1 and the other side was attached to a TAC film of 40 thickness to prepare a polarizing plate in the same manner as in Example 4. Comparative Example 3 A polarizing plate was prepared by laminating a TAC film having a thickness of 40 on both sides of the PVA film by laminating with the PVA film so that the thickness of the adhesive layer was approximately 1 using an acrylic adhesive.

Experimental Example

 <Measurement method>

 1) Thickness

 Measurement was made using a digital micrometer.

2) transmittance

 The transmittance and the haze were measured using a Hazemeter (HM 150).

3) phase difference

 The retardation value was measured using a phase difference measuring instrument (Axoscan).

4) pencil hardness

 Using a pencil hardness tester, the surface of the polarizing plate was reciprocated five times with a load of 500 g according to the measurement standard JIS K5400, and then the hardness without grooves was confirmed.

5) Scratch Resistance

 A constant load was placed on steel wool # 0000 and reciprocated 10 times to check the load without grooves.

6) Curl Characteristics

 Each polarizing plate was cut into 10 cm × 10 cm, and stored at room temperature for 24 hours, and then the average value of the distance from which one side of each corner is spaced apart from the plane was measured.

7) Cylindrical bend test After each polarizing plate was wound in a cylindrical mantel having a diameter of 5 mm, cracks were judged to determine whether or not cracks were generated. The physical property measurement results are shown in Table 1 below.

 Table 1

As shown in Table 1, the polarizing plate of the embodiment of the present invention exhibited good properties in all the physical properties. In particular, compared with the conventional protective film including TAC and coating layer and Comparative Example 3 including only TAC, as in Comparative Example 2, it exhibits high hardness, excellent curl characteristics, flexibility, low phase difference, etc. at a low thickness, and requires thinning. It can be usefully used for the display device.

Claims

[Patent Claims]

 [Claim 1]

 A binder comprising the multifunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and an acrylate elastic polymer; And

 Resin composition containing a photoinitiator.

[Claim 2]

 According to claim 1,

 When the total amount of the binder is 100 parts by weight, 20 to 70 parts by weight of the polyfunctional acrylate monomer, 20 to 70 parts by weight of an acrylate oligomer having an elongation of 5 to 200%, and the acrylic A resin composition comprising 1 to 50 parts by weight of the rate-based elastic polymer and 1 to 10 parts by weight of the photoinitiator.

[Claim 3]

 The method of claim 1,

The polyfunctional acrylate monomers include nucleic acid diol diacrylate (HDDA), tripropylene glycol diacrylate (TPGDA), ethylene glycol diacrylate (EGDA), trimethyl to propane triacrylate (TMPTA), and trimethyl to propane. Specially Triacrylate (TMPEOTA), Glycerin Propoxylated Triacrylate (GPTA) _: Pentaerythrine selected from the group consisting of tetraacrylate (PET A), and dipentaerythrine nuxaacrylate (DPHA) Resin composition containing 1 or more types.

[Claim 4]

 According to claim 1,

The acrylate oligomer has two or more acrylate functional groups and has ethylene oxide and propylene oxide. oxide) and caprolactone (caprolactone) is a resin composition modified by at least one selected from the group consisting of.

[Claim 5]

 The method of claim 1,

 The acrylate-based elastic polymer is a resin composition having an elongation of 5 to 200%.

Γclaim 6

 According to claim 1,

 The acrylate-based elastic polymer is a resin composition comprising at least one of polyrotasein or urethane acrylate-based polymer.

[Claim 7]

 According to claim 6,

 The polyrotasein may be a cyclic compound having a caprolactone group having an acrylate compound introduced therein; Linear molecules penetrating the cyclic compound; And a blocking group disposed at both ends of the linear molecule to prevent the cyclic compound from leaving.

[Claim 8]

 The method of claim 1,

 A resin composition further comprising an organic solvent.

[Claim 9]

 According to claim 1,

 The resin composition used to form a polarizer protective film.

[Claim 10]

Multifunctional acrylate monomer, having elongation of 5 to 200% A polarizer protective film containing a cured resin with an acrylate-based oligomer and an acrylate-based elastic polymer.

[Claim 11]

 The method of claim 10,

 The cured resin is 20 to 70 parts by weight of the acrylate-based oligomer having 20 to 70 parts by weight of the polyfunctional acrylate monomer, the elongation of 5 to 200% when the total weight of the cured resin to 100 parts by weight The polarizer protective film wherein the acrylate-based elastic polymer is cured to 1 to 50 parts by weight.

[Claim 12]

 The method of claim 10,

The polyfunctional acrylate monomers include nucleic acid didi diacrylate (HDD A), tripropylene glycol diacrylate (TPGDA), ethylene glycol diacrylate (EGDA), trimethyl to propane triacrylate (TMPTA), trimethyl pro Tube specific triacrylate (TMPEOTA), glycerin propoxylated triacrylate (GPTA) pentaerythritol is selected from the group consisting of tetraacrylate (PETA), and dipentaerythride nuxaacrylate (DPHA) one polarizer protective ^"film that includes more species.

[Claim 13]

 The method of claim 10,

 . The acrylate oligomer has at least two acrylate functional groups and is a polarizer protective film modified by at least one selected from the group consisting of ethylene oxide, propylene oxide and caprolactone. .

[Claim 14] The method of claim 10,

 The acrylate-based elastic polymer is a polarizer protective film having an elongation of 5 to 200%.

[Claim 15]

 The method of claim 10,

 The acrylate-based elastic polymer is a polarizer protection, film comprising at least one of polyrotasein or urethane acrylate-based polymer.

[Claim 16]

 The method of claim 15,

 The polyrotasein may be a cyclic compound having a caprolactone group having an acrylate compound introduced therein; Linear molecules penetrating the cyclic compound; And a blocking group disposed at both ends of the linear molecule to prevent separation of the cyclic compound.

[Claim 17]

 Polarizer; And

 And a protective film provided on at least one surface of the polarizer, wherein the protective film comprises a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and a cured resin with an acrylate elastic polymer. Polarizing plate containing.

[Claim 18]

 The method of claim 17,

When the total weight of the cured resin is 100 parts by weight, the cured resin is 20 to 70 parts by weight of the polyfunctional acrylate monomer, 20 to 70 parts by weight of the acrylate oligomer having an elongation of 5 to 200% The polarizing plate, wherein the acrylate-based elastic polymer is cured to 1 to 50 parts by weight.

[Claim 19]

 The method of claim 17,

The polyfunctional acrylate monomers include nucleic acid didi diacrylate (HDDA), tripropylene glycol diacrylate (TPGDA), ethylene glycol diacrylate (EGDA), trimethylolpropane triacrylate (TMPTA), and trimethylolpropane. Roxy triacrylate (TMPEOTA), glycerin propoxylated triacrylate (GPTA) _: 1 type selected from the group consisting of pentaerythriri tetraacrylate (PETA), and dipentaerythrine nuxaacrylate (DPHA) Polarizing plate containing the above.

[Claim 20]

 The method of claim 17,

 The acrylate oligomer is a polarizing plate having at least two acrylate functional groups and modified with at least one selected from the group consisting of ethylene oxide, propylene oxide and caprolactone.

[Claim 21]

 The method of claim 17,

 The acrylate-based elastic polymer is a polarizing plate having an elongation of 5 to 200%.

[Claim 22]

 The method of claim 21,

 The acrylate-based elastic polymer is a polarizing plate comprising at least one of polyrotasein or urethane acrylate-based polymer.

[Claim 23]

The method of claim 22, The polyrotasein may be a cyclic compound having a caprolactone group having an acrylate compound introduced therein; Linear molecules penetrating the cyclic compound; And a blocking group disposed at both ends of the linear molecule to prevent separation of the cyclic compound.

[Claim 24]

 The method of claim 17,

 A polarizing plate 더 further comprising an adhesive layer provided between said polarizer and said protective film.

[Claim 25]

 The method of claim 17,

 The protective film has a thickness of 10 to 100Λΐι polarizing plate.

[Claim 26]

 The method of claim 17,

 The polarizing plate has a thickness of 45 to 250.

[Claim 27]

 The method of claim 17,

 Polarizer showing a pencil hardness of more than ΙΗ at 500g load.

[Claim 28]

 The method of claim 17,

 The polarizing plate having an average value of distances spaced from each corner or one side of the polarizing plate when the image is positioned on the flat surface after exposure for 24 hours at about 3 mm or less.

[Claim 29]

The method of claim 17, A polarizer that does not cause cracks when wound into a cylindrical mandrel with a diameter of 15 mm.

[Claim 30]

 A binder comprising a polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, and an acrylate elastic polymer on a release film; And applying a resin composition comprising a photoinitiator; Photocuring the applied resin composition to form a protective film; And

 Method for manufacturing a polarizing plate comprising the step of laminating and bonding the protective film on one surface of the polarizer

[Claim 31]

 The method of claim 30,

 Peeling the release film before or after the step of laminating the protective film on one side of the polarizer and after bonding.